[Boost-users] [Regex] Empty regular expression

Hello boosters, First, apologies if this has been discussed before - I did some googling and could not find it. I've bumped into an interesting issue while using Boost.Regex. The documentation states: http://www.boost.org/libs/regex/doc/basic_regex.html Effects: Constructs an object of class basic_regex. The postconditions of this function are indicated in the table: Element Value empty() true size() 0 str() basic_string<charT>() Using 1.33, I get empty() set to false with the default constructor. In addition, if you attempt to search using an empty regex, the program segfaults. The following example demonstrates the problem: code: ------ #include <iostream> #include <string> #include int main() { std::string line("this is an example line"); boost::smatch what; boost::regex re; std::cout << "re.empty(): " << re.empty() << std::endl; bool result = boost::regex_search(line, what, re); } output: ------ re.empty(): 0 Segmentation fault This does not happen if I initialize the regex using an empty string (it throws empty expression). Which leads to the main question (and the reason why I discovered all of this): is it possible to make a regular expression that matches anything? For instance, when using AWK, if you define a rule without a pattern, i.e.: { print $0; } I thought an empty regex would do the trick. Regards, Marco -- in software development, the design document is a source code listing. -- jack reeves